VW Engineering International

Cogeneration, the combined generation of heat and power, is an efficient method to reduce cost or to save energy and hence, reduces the pollution. A large number of thermal process industries have this option to install cogeneration system and sugar mill is one of them. In this work, energy and exergy analysis of a sugar mill running on cogeneration system, having back pressure turbine system, has been carried out. Based on the operational data received from the industry, the detailed analysis of the system has been performed. It was found that the output power and excess power of the plant increases with increase in the boiler pressure and therefore, increases the cogeneration efficiency. Also, it was noticed that when the back pressure increases, the turbine output and cogeneration efficiency decrease and, Heat to Power Ratio (HPR) spans over a range of 2.79 to 4.07. From the exergy analysis of the plant, it is observed that the boiler is the main component for exergy destruction. The energy analysis of bagasse fired boiler was carried out and the results showed that energy efficiency was high up to 84.5%. However, the second law efficiency gave 28.5% and irreversibility rate associated with the combustion chamber was 62.19 MW which accounts 55.09% of the total fuel exergy.

Abstract: The purpose of this study is to see how carbon fiber and graphite reinforcement affects the strength, wear, hardness, etc. of the ZA-27 alloy. The stir casting process was used to create composites containing carbon fiber and graphite particles. Using a block-on-disk tribometer, the tribological characteristics of unreinforced alloys and composites were investigated at various specific loads and sliding speeds. In all combinations of applied loads (Fn) and sliding speeds (v) in testing, the ZA-27/ graphite composite specimens displayed much lower wear performance than the matrix aluminum specimens. Nonuniform triboinduced graphite films were generated in test circumstances defined by a low graphite content and low sliding speeds and applied loads, resulting in a rise in the friction coefficient and wear rate as the sliding speed and applied load increased. It was found that reinforced samples performed better tribologically. Carbon fiber and graphite reinforced ZA-27 may find new applications in various machine parts in the industry.

The study's goal is to see how mechanical, wear, and thermal characteristics of ZA-27 alloy composites are all affected by macroscopic carbon fiber particles. The composites were made using the compo casting process, with carbon fiber particles used to strengthen the ZA-27 alloy. Under unlubricated circumstances, the pin on the disc equipment was subjected to wear testing at varied loads and speeds. With the addition of Carbon Fibre particles, it was discovered that the tribological quality improves. However, based on the results of the other parameters, in order to obtain better performance, the percentage of reinforcing must be tuned depending on the application requirements, and composites may be utilized as structural materials in a number of applications, including bearings and temperature control functions.

Landslides are one of the most recurrent natural hazards occurring each year in the hilly and mountainous regions of Nepal causing massive loss of life and property. Natural hazards such as landslides cannot be avoided completely but the processes and consequences can be mitigated. The main objective of the study was on the application of Geographic Information System (GIS), and statistical calculations for landslide susceptibility modeling of Gulmi District, western Nepal. The models were derived using two different statistical approaches including Frequency Ratio (FR) and Shannon Entropy (SE). A landslide inventory of the Gulmi district was developed. The landslide inventories were used to derive the quantitative relationships between landslide occurrences and landslide causative factors. In this study, ten landslide influencing factors were used which include slope, aspect, curvature, lithology, geology, land use land cover, distance from the river, distance from the road, and distance from fault and soil type. Individual factor maps were prepared as thematic layers. After determining the weights of each class from the proposed two models, the landslide susceptibility maps were ready with five classes (very low hazard, low hazard, moderate hazard, high hazard and very high hazard) using GIS. The values of Area Under Curve (AUC) of success rate for FR and SE methods were found to be 81.8% and 80.6% respectively. The model shows that more than 15 % of the area falls under low and very low susceptibility level while 44% of the area has a high probability of landslide occurrence. The result of the present study indicates that integration of GIS has increased the quality and effectiveness of the overall process of susceptibility modeling and prediction mapping. To enhance the planning strategies for disaster mitigation and ensure sustainable development a reliable landslide hazard forecasting and risk assessment is a key component.

Intermittency in solar energy, in case of thermal applications, it is necessary to store this energy in the form of thermal energy. It can be used when solar energy is unavailable and thus helps in minimizing the mismatch between energy demand and supply. However, it has poor heat transfer characteristics resulting in more charging and discharging times. To address this issue, various methodologies related to heat transfer enhancement have been suggested. Moreover, suitable working parameters for the best performance of this thermal storage system are also obtained. The results obtained under the present study revealed that additions of longitudinal fins improve the system efficiency significantly by reducing the charging and discharging times. Better performances were observed at a higher value of inlet temperature and mass flow rate of HTF. Moreover, suitable working parameters for the best performance of this thermal storage system are also obtained.